He said: "This is another example of Birmingham's failure to promote itself and make a real effort to get these things, following the fiasco of the casino bid."

Marketing Birmingham said parties traditionally demanded the use of conference halls either for free or vastly reduced rates.

Neil Rami, Marketing Birmingham's chief executive, said: "In a sense we are a victim of our own success as hosting the conference becomes commercially viable for a venue only when it has vacancies which are not being filled." n It is a conference tradition that politicians praise whichever town or city is hosting the event.

Trade Industry Alistair Darling kept up the tradition when he named Manchester as the heart of the industrial revolution.

But that might come as a surprise to residents of Midland towns such as Ironbridge - commonly known as the Birthplace of the Industrial Revolution.